Deep sea submarine cable



Feb. 10, 1959 H. HORN DEEP SEA SUBMARINE. CABLE Filed May 7, 1954 POL V57' YPOI.

5 E m w H To 40 m P a 5 5M Y Wm m 4 P 5 AL UM/IV/l/M ZZZ,U 6111 02fjfiorzz/ United States Patent DEEP SEA SUBMARINE CABLE Heinz Horn,

Koln-Mulheim,

ten & Guilleaume Carlswerk Ak Mulheim,

Germany Germany, asslgnor to Fe!- tiengesellschaft, Kohl- Submarinecables used, for i sion of normal telegraphic cu .acopper conductor, aninsulat sion of high frequency curren is additionally prov In the caseof ca ing fulfills a double of the ship, like.

above mentioned do not exist.

ing serves only for has to be taken up Bearing in mind insulatingmaterial, with respect to the specific the ided unde bles used purpose:

along 2 Claims. (CL 174 l02) nstance, for the transmisrrents generallyconsist of ion and, if necessary, also I ts, a copper return conductor rthe armouring.

the coast, the armourthis case, the armourtaking up tensional forcesduring the laying and is important only once more when the cable againfor the purpose of repairs.

laying sible. It is known to use profile as the armouring m to its smallspecific weight,

a multiple In water it amounts styrol strand is wire.

great water depth, th

For this reason, the present with material.

It would therefore be desir sea cable in which in orde armouring, otherconstructi deep sea cables ha armouring strands aterial.

submarine cable could be used.

It has already been which in the case of length of copper in of theknown deep s is used to take up of pure copper but submarine ships thatare at ones disthe drfiiculties encountered during of steel wires ofgreat curing, the weights are always case of great water depths.

whereby the strength of the latter weight shall be as great asposstrands of polystyrol It has been found that, owing the tearinglength of a polyof the tearing length of steel. to about 140 klm.

ey have no further function to fulfill. ve not been laid up to made of asynthetic able to manufacture a deep 1' to fulfil the task of the onalelements of the deep proposed to-use the inner conductor, cablesgenerally consists water is only 2500 meters, in the case ea cables, inwhi ch the inner conductor the tensional forces, use is not made of acopper all oy of correspondingly 2,873,307 Patented Feb. 10, 1.959

greater strength. Of course, this alloy has the disadvantage that itsconductivity is substantially smaller as compared with that of purecopper.

According to the invention, use is made of a submarine cable, moreparticularly a deep sea cable, in which the insulation is made of suchtensional strength that it takes up the function of the armouring of adeep sea cable, so that the outer armouring can be dispensed with.

This construction of cable has substantial advantages as compared withthe known deep sea cables. On the one hand, use can be made of an innerconductor which is of pure copper and of the best conductivity and, onthe other hand, outer armouring wires are rendered superfluous, so thatthe diameter and the Weight can be reduced even in the case of cableswith small damping to such an extent that they can be handled with thelaying ships and laying means which are at ones disposal. Moreover,there is the advantage that the strands which are used for taking up thetensional forces do not lie uselessly at the bottom of the sea after thelaying but constitute a portion of the insulation.

The insulation has to be such, that it is capable of supon the otherhand, the elastic behaviour of this substance is such that the copperconductor cannot be excessively extended.

The polystyrol is preferably used in a stretched condition, in the formof a strand of circular or profile shape stretched on one side, or inthe form of a band stretched on both sides. In order that theirtensional strength may be fully utilised the strands or bands ofpolystyrol have to be applied with a long lay on the central copperconductor. The strands or bands have to substantially fill up theintermediate spaces between the central copper conductor and an outercylindrical and water tight sheathing, for instance of polyethylene. Anyspaces left between the strands or bands are preferably filled by aviscous insulating material, for instance a mixture of polyethylene andpolyisobutylene, in order that the hydrostatic pressure of the watershall be uniformly distributed. The advantage of bands stretched on bothsides, as compared with strands of polystyrol stretched on one sideonly, is that the bands have a substantially higher resistance topressure owing to the stretching on both sides.

In order to obtain a cable been found advisable in the stranded in anumber of layers to strand them with alternating direction of lay fromlayer to layer.

As regards the cable sheathing, use may advantageously be made, forinstance, of polyethylene and to apply the outer conductor on the cablesheathing in the form of copper Wires and bands. It is also advantageousto use a metal cable sheathing, for instance, an aluminium tube,

which may serve at the same time as a return conductor.

The invention is illustrated, by way of example, in connection with theconstructions shown in Figures 1 and 2 of the accompanying drawings.

According to Figure 1, the cable core consists of a conductor 1comprising one or a number of copper wires, on which there is stranded alayer of polystyrol strands 2 with a long lay. Thereon there is strandeda further layer of polystyrol strands 3, also with a long lay, but inthe opposite direction. The intervening spaces between the coppolystyrolwires are filled with an insulating compound 4. This compound may forinstance consist of a mixture of polyethylene and polyisobutylene. Thecable is surrounded by a water-tight sheathing 5,

G which may preferably eonsist of polyethylene. Flatcopper wires 6 arethen stranded over the cable sheathing to act as a return conductor.There also follows as is known per se, one or two layers of jute 7.Outer 'armouring wires are not .provided.

Figure 2=shows another example of construction according to theinvention. 7 The same differs from the example .of construction shown in:Figure .1 only :byzthis that,'insteadof'thecablesheathingofpolyethylene, use is made of a sheathing 5' ofaluminium or aluminiumalloy. V

The'sheathing can then serve-at the same time as areturn conductor, sothat the use of'fiat'copper wires 6 is rendered superfluous.

-I claim:

1. Asa newarticle of manufacture a deep submarine cable'without theusualprotective covering, consisting of an inner conductor, at-combinedinsulation'and tension-ab- ;sorbing'armouring means-around saidconductor consisting of inner and outer supe'rimposed layers of.polystyrene pror filed strands str'etched ion both-sides with difierentlay directions 'and a relativelylong-laying length and of such .greattensile strength to'serve also -as an armor for the cable withoutthe-use of additional armourin'g steel wires, a

watertight sheathing around said insulation, a-"viscous'insulatingmixture of polyethylene and polyisobutylene in the spaces between thesaid strands, the inner conductor, and the sheathing, and an outerreturn conductor around the water-tight sheathing.

2. A submarine cable as claimed in claim 1, characterized by that thecable sheathing'consists of polyethylene.

References Cited in the file of this patent UNITED STATES "PATENTS OTHERREFERENCES 7 :Modern :Plastics publieation), Iuly 211944; :pagei', (InDiv. "69.) -174-110:4. t

1. AS A NEW ARTICLE OF MANUFACTURE, A DEEP SUBMARINE CABLE WITHOUT THEUSUAL PROTECTIVE COVERING, CONSISTING OF AN INNER CONDUCTOR, A COMBINEDINSULATION AND TENSION-ABSORBING ARMOURING MEANS AROUND SAID CONDUCTORCONSISTING OF INNER AND OUTER SUPERIMPOSED LAYERS OF POLYSTYRENEPROFILED STRANDS STRETCH ON BOTH SIDES WITH DIFFERENT LAY DIREACTION ANDA RELATIVELY LONG LAYING LENGTH AND OF SUCH GREAT TENSILE STRENGTH TOSERVE ALSO AS AN ARMOR FOR THE CABLE WITHOUT THE USE OF ADDITIONALARMOURING STEEL WIRES, A WATER-TIGHT SHEATING AROUND SAID INSULATION, AVISCOS INSULATING MIXTURE OF POLYETHYLENE AND POLYISOBUTYLENE IN THESPACES BETWEEN THE SAID STRANDS, THE INNER CONDUCTOR, AND THE SHEATING,AND AN OUTER RETURN CONDUCTOR AROUND THE WATER-TIGHT SHEATHING.